textproduct: Albany

WHAT HAS CHANGED

Wind Advisory expanded to include northern Fulton and Northern Saratoga Counties from this evening into Monday morning.

KEY MESSAGES

1. Scattered snow squalls and lake effect snow this afternoon and evening, potentially leading to brief/localized hazardous driving conditions.

2. Gusty west to northwest winds of 35 to 50 mph developing this evening into tonight may lead to some downed tree limbs and possible power outages.

3. A clipper system brings rain and/or snow showers Tuesday into Wednesday, followed by a pattern change with colder temperatures and potential snowfall later in the week.

DISCUSSION

KEY MESSAGE 1...

Radar, obs and webcams indicating a broken line of snow showers and squalls moving east across central NY early this afternoon. These have developed along the leading edge of an upper level trough axis and ahead of a surface cold front pushing SE across Lake Ontario. Forcing is decent and 0-3 km, lapse rates are steep at ~7 to 8C/km, but some mitigating factors to more widespread squalls include limited moisture along with fairly mild surface/ground temperatures(mid 30s to lower 40s) especially from the Hudson Valley east. Still, the potential for scattered snow squalls exists between 2 PM to 8 PM across eastern New York and western New England. Sudden lowering of visibility to 1/4 mile, along with wind gusts of 30-40 mph, rapid temperature drop to below 32F and a quick coating of snow can create brief/localized hazardous driving conditions within any snow squalls this afternoon into early evening.

Upslope/lake enhanced snow showers will likely linger through this evening mainly across parts of the W. Adirondacks, W. Mohawk Valley and S. Green Mountains in the NW cyclonic flow regime. Only an inch of so of snow accumulation is expected in these areas, with 1-3" in the W. Adirondacks.

KEY MESSAGE 2...

In wake of the upper trough axis passage and surface cold front winds will increase this evening into tonight, as the pressure gradient and wind speeds aloft strengthen. Cold advection will promote decent mixing, even with mixing heights lowering. Winds ~50 mph near the top of the mixed layer will potentially mix down to the surface in the Wind Advisory area, with channeling expected in typically favored areas in W-NW flow such as the Mohawk Valley and Capital District into the Berkshires. Only change to the Wind Advisory was to expand slightly northward into N. Fulton and N. Saratoga Counties. Wind gusts will decrease below advisory criteria(< 46 mph) around or shortly after sunrise Monday. Westerly winds will gust between 20-35 mph through much of the day though.

KEY MESSAGE 3...

After some additional minor lake effect snow (additional 1-3") across northern portions of Herkimer/Hamilton Counties Mon afternoon into Mon night, attention then turns to a clipper system tracking SE across the upper Great Lakes into S. Ontario/Quebec Tue through Tue night. With the parent cyclone expected to track well north of our area, temperatures will remain above normal with thermal profiles indicating mainly rain showers for lower elevations and rain/snow showers in the higher terrain. Better forcing looks to arrive Tue night, although with limited moisture mainly light QPF is anticipated. Upslope SW flow could lead to some enhancement in the S. Adirondacks with some minor snow accumulation there.

As a cold front associated with the clipper gradually start to sag south across our area on Wed, chances for rain/snow showers will continue. Again lower elevations should be mild enough for rain, with rain/snow mix in the mountains. Forecast confidence then lowers as a wave of low pressure may develop along the front as it stalls near the mid Atlantic region. There could be enough baroclinicity for cyclogenesis near the Delmarva in the Wed night through Thu night time frame. Depending on the evolution/track of this system there some accumulating snow is possible in our area. Current NBM probabilities are 30-50% for > 2" of snow and 10-40% for > 4". At this time, the bulk of heavy precip looks to be south/east as the expected upper trough position favors more a substantial cyclone offshore. Will continue to monitor trends over the next few days.

AVIATION /18Z SUNDAY THROUGH FRIDAY/

Through 18z/Mon...VFR conditions will start the TAF period at all sites before a cold front moves through prior to 00z/Mon. Snow showers and embedded squalls will accompany the front and cross the TAF sites between 21z/Sun and 02z/Mon. Brief reductions in visibilities to IFR or even LIFR could occur should one of these showers pass over a TAF site. Confidence remains moderate to high for these showers to reach KALB/KPOU/KPSF with lower confidence at KGFL. PROB30 groups were maintained but reduced to 1-hour lengths to highlight the most likely arrival time for these showers as any reductions will be brief (generally 30 minutes or less). After the front passes and snow showers end, mixed MVFR/VFR cigs are expected into the overnight hours (highest confidence for MVFR cigs at KPSF) before decreasing clouds lead to returned VFR conditions by 12z/Mon.

Winds will be westerly at around 10 kt with a few gusts to 20 kt this afternoon prior to the cold frontal passage. Behind the front (and possibly within any snow squalls), winds will increase to 15-25 kt with gusts 30-40 kt. Winds will begin to gradually subside late tonight and become more west to southwesterly for Monday morning.

Outlook...

Monday Night: No Operational Impact. NO SIG WX. Tuesday: No Operational Impact. NO SIG WX. Tuesday Night: Moderate Operational Impact. Chance of SHRA. Wednesday: Moderate Operational Impact. Chance of RA. Wednesday Night: Moderate Operational Impact. Likely RA...SN. Thursday: High Operational Impact. Likely RA...SN. Thursday Night: Moderate Operational Impact. Chance of SN. Friday: Low Operational Impact. Slight Chance of SN.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...Wind Advisory from 5 PM this afternoon to 9 AM EST Monday for NYZ038>041-047>054-058>061-082. MA...Wind Advisory from 5 PM this afternoon to 9 AM EST Monday for MAZ001-025. VT...None.